The Scientific Committee, established by the Threatened Species Conservation Act, has made a Final Determination to list the Sydney Freshwater Wetlands in the Sydney Basin Bioregion as an ENDANGERED ECOLOGICAL COMMUNITY on Part 3 of Schedule 1 of the Act. The listing of Endangered Ecological Communities is provided for by Part 2 of the Act.

The Scientific Committee has found that:

1. Sydney Freshwater Wetlands is the name given to the plant community characterised by the assemblage of species listed in paragraph 2 that is restricted to freshwater swamps in swales and depressions on sand dunes and low nutrient sandplain sites in coastal areas. All sites are within the Sydney Basin Bioregion.

2. Sydney Freshwater Wetlands is characterised by the following assemblage of species.

Banksia robur

Baumea articulata

Baumea juncea

Baumea rubiginosa

Callistemon citrinus

Casuarina glauca

Cladium procerum

Eleocharis sphacelata

Empodisma minus

Gahnia clarkei

Gahnia sieberiana

Gleichenia dicarpa

Goodenia paniculata

Hakea teretifolia

Hypolepis muelleri

Lepironia articulata

Leptocarpus tenax

Leptospermum juniperinum

Lomandra longifolia

Ludwigia peploides subsp. montevidensis

Melaleuca linariifolia

Melaleuca nodosa

Melaleuca quinquenervia

Melaleuca styphelioides

Persicaria decipiens

Persicaria strigosa

Philydrum lanuginosum

Phragmites australis

Pteridium esculentum

Restio tetraphyllus

Schoenus brevifolius

Triglochin procerum sensu lato

Typha orientalis

Villarsia exaltata

Viminaria juncea

Xanthorrhoea resinifera

3. The total species flora and fauna list for the community is considerably larger than that given in 2 (above), with many species present in only one or two sites or in very small quantity. In any particular site not all of the assemblage listed in 2 may be present. Invertebrate species may be restricted to sediments for example. At any one time, propagules and seeds of some species may only be present in the soil seed bank with no above-ground individuals present. The species composition of the site will be influenced by the size of the site, recent rainfall or drought conditions and by its recent disturbance history. The community includes vertebrates and invertebrates, many of which are poorly known.

4. Sydney Freshwater Wetlands are a mosaic community with considerable variation due to fluctuating water levels and seasonal conditions. Characteristic vegetation is sedges and aquatics particularly Eleocharis sphacelata, Baumea juncea, Baumea rubiginosa, Baumea articulata, Gahnia sieberiana, Ludwigia peploides subsp. montevidensis and Persicaria species. There may be considerable areas of open water particularly where drainage conditions have been altered. There may be patches of emergent trees such as Melaleuca quinquenervia and shrubs.

5. Sydney Freshwater Wetlands are restricted to freshwater swamps in swales and depressions on sand dunes and low nutrient sandplain sites in coastal areas. These areas are generally on the sands of the Warriewood and Tuggerah Soil Landscapes (Chapman & Murphy 1989). Coastal Swamp Forest eg. Eucalyptus robusta and swamp on alluvium with a saline influence is not covered by this Endangered Ecological Community Determination.

6. Sydney Freshwater Wetlands are or have been known to occur in the local government areas of Lake Macquarie, Wyong, Gosford, Pittwater, Warringah, Woollahra, Waverley, Botany, Rockdale, Randwick, Sutherland and Wollongong- but may occur elsewhere in the Sydney Basin Bioregion.

9. Disturbed remnants are considered to form part of the community described under this determination where the natural soil and associated seedbank is partially intact. At some sites changes to hydrology or drainage may be required to assist regeneration.

13. In view of the small size of existing remnants, and the threat of further clearing, disturbance and degradation, the Scientific Committee is of the opinion that the Sydney Freshwater Wetlands in the Sydney Basin Bioregion are likely to become extinct in nature in New South Wales unless the circumstances and factors threatening its survival or evolutionary development cease to operate and that listing as an endangered ecological community is warranted.